Damper construction



July 5 w. A. SCHMIDT DAMPER CONSTRUCTION Filed Nov. 22. 1924 z et -sh 1 A TTORNEY.

Patented July 5, 1927.

1,634,559 Fries.

A'rEr -WALTER A. SCHMIDT, DE LOS ANGELES, CALIFORNIA, ASSIGNOR TO INTERNATIONAL PRECIPITATION COMPANY, OF L'GS ANGELES, CALIFORNIA, A CORPORATION OF CALIFORNIA.

.DAQMZEER CONSTRUCTION.

Application filed November 22, 1924. Serial No. 751,648;

This invention relates to dampers for use in controlling or regulating the flow of hot gases, for example for controlling the flow of flue gases from a furnace or kiln to the stack. to provide a damper for this purpose which will be able to withstand high temperatures without damage or deterioration.

If an ordinary metal damper is used in a flue through which gases at high temperatures are passing, for example in theoutlet flue of a furnace, the metal is badly warped and sometimes cracked by such high temperatures, and the damper soon becomes unfit for operation or ineffective. It has been attempted to cover such metal dampers with coatings of refractory material but this is of little benefit for the heat from the gases soon penetrates such refractory mate rial and damages the metal frame or supporting plate almost to the same extent as though the bare metal were used.

I have found however that by providing a metal frame and supporting a slab or wall of refractory material upon such frame, and providing suitable means whereby said metal frame is maintained entirely outside the path of the hot gases at all times such metal is prevented from overheating and a permanent durable construction is thus obtained.

The accompanying drawings illustrate embodiments of my invention and referring thereto:

Fig. 1 is a transverse vertical section through a flue and damper according to my invention.

Fig. 2 is a vertical section on line 22 in Fig. 1, partly broken away.

Figs. 3 and 4: are horizontal sections on lines 33 and 4l-4l respectively in Fig. 1.

Fig. 5 is a partial. transverse vertical section through the lower portion of a damper involving a slightly different construction.

Fig. 6 is a partial horizontal sectiomsimilar to Fig. 4, of the form of damper shown in Fig. 5. y t

A flue through which hot gases are to pass is indicated at l and is shown as provided with hoppers 2 'at the bottom for col lection and removal of solid material deposited from such hot gases. Said flue may lead, for example, from the combustion chamber of a furnace to the stack, or from i a kiln to a stack or to a dust precipitating The main object of the invention is 7 apparatus. The flue may be constructed of refractory brick laid up and supported in any suitable manner, for example, as indicated, or the flue may be built of iron or steel or other material, lined if necessary, with refractory brick. At the point in said flue where the damper is to be located an enlarged portion or housing section 3 is provided, which affords lateral recesses or pockets at extending outwardly beyond the side walls 5 of the flue and a downwardly projecting recess or housing portion 6 below the bottom wall of the flue. The lateral recesses or pockets 4 project upwardly above the top of the-flue as indicated at 21 for the purpose forth below. Said lateral recesses are adapted tocontain the side bars of the damper frame and protect the same from the hot gases passing in flue l and the (,lownwardly projecting housing portion 6 is adapted to contain and protect the base or lower frame member of the damper frame. Thehousing section 3is preferably made of metal or other heat conducting material so as to permit dissipation of heat from the parts of the metal damper frame. Said damper frame may comprise upper andv lower horizontal frame members 7 and '8 and vertical frame members or supporting bars 9. Said vertical frame members project through openings 10 in the top. of the upwardly extending portions of the lateral pockets 4 of housing 3, such openings being provided with suitable means indicated at 11 for preventing or reducing leakage of gas theretl'irough. The damper body itself comprises a slab or wall structure 12'of suitable dimensions and composed of heat resistant or refractory material mounted upon the lower frame member 8 and between and around the vertical frame members 9. The construction is such that said slab or wall structure 12 may be entirely lowered within the downwardly extending housing 6 if desired so as to leave the normal flue opening entirely unobstructed, or said slab 12may be raised so asv to obstruct the passage of gas through the flue to any desired extent. 'The height of the refractory slab 12 should be suflicient to permit full closure.

of the damper without causing the lower frame member 8 to be raised up above the bottom of the flue indicated at 13 and the depth of the recess or housing portion 6 is sufficient to enable the damper to be lowered to position to open the flue or to be raised to position to close the flue while maintaining the lower metal frame member 8 at all times wholly within said lower housing portion and outside of the flue. It is to be noted that the top of the refractory wall means 12 of the damper, which is necessarily exposed to the full heat of the flue gases, does not contain and does not require any metallic supporting means therein. The construction is therefore such that, regardless of the position which the damper may occupy in the flue, the portion of the damper which is within the cross-section of the flue is composed entirely of refractory material, and there are at no time any metal parts within the cross-section of the flue. Suitable means indicated at 14; may be provided for raising 0r lowering the damper so as to close or open the flue. The downwardly extending housing 6 may be provided at its bottom with means such as sliding gate 15 for permitting removal of any solid material deposited in said housing from time to time.

The refractory slab 12 which constitutes the damper body proper may consist of refractory material, such as refractory clay or cement or other suitable heat resisting material and may be made in one piece molded to the proper shape and then burned, but said damper body is preferably built up of refractory bricks or eleme. ts 16, said bricks being bonded together with any suitable refractory mortar or high temperature cement. If desired, in order to incr the strength of the refractory slab or ture, the bricks may be provided v. able interlocking means, such as tongue and groove means, so as to assist the mortar in holding said bricks in place. Said slab 12 or the outermost bricks or member which the same is built up may be provided with vertical slots or recesses 17 through which the vertical frame members 9 may extend.

Each of said frame members 9 may be provided on the side toward the flue with a protective covering 18 of refractory or heat resistant material. in order to still further protect said frame members from the hot gases and prevent damage to the same. Such protective covering may be provided for example by extending the outermost rows of bricks, of which the damper body is built, upwardly above the top of the main damper slab itself, and the protective coverings so formed should extend high enough so that said vertical frame members will be fully protected from the hot gases even when the damper is lowered to full open position as shown in the drawings. The bricks used for this purpose may be provided with openings, such as slots or notches 19, through which the vertical frame members pass, so that said frame members help to hold the bricks in position, while leaving as much of the metal frame members exposed as possible on the side away from the fine so as to permit dissipation of heat therefrom by radiation and convection. Said slots or notches may be of suflic-ient size to permit the bricks to he slipped over and around said frame members from the side. If the damper is made of a single slab or unit of refractory material, said slab may be provided with upwardly extending portions adapted to protect the vertical frame members in a similar manner, or separate refractory blocks or slabs of suitable shape may be used for this purpose. In any case, however, the refractory covering should be so formed as to completely protect the vertical frame members on the side toward the flue, and to leave as much of said members exposed as possible on the side away from the flue, so as to permit the maximum cooling thereof by radiation and convection.

The lateral recesses 4: should extend upwardly above the flue sufficiently to permit movement therein of the refractory covering means 18 when the damper is'raised to full closed position. Furthermore the shape and size of said recesses and the upward extensions thereof should be such as to make as close a fit as is practicable around said re fractory covering means so as to prevent as far as possible the passage of the hot gasesfrom the flue into said recesses and upward extensions and around the unprotected portions of the vertical frame members. In the same manner, the downwardly extending portion 6 of the housing should fit fairly: closely around the damper slab, so as to prevent access of hot gases tov the lower frame member 8 and also to minimize the deposition of dust in the bottom of the housing.

In the use of the above described damper in operation, it will be noted that. whatever position the damper may be made to assume in the flue, the metal frame members 7, 8, and 9 will be entirely outside the cross sec tion of the flue proper and will be fully protected by refractory material from the'hot gases passing' through the flue, so that such hot gases will have little if any access to said frame members. The upper frame member 7 is of course entirely outside the flue and therefore subject to nov hot gases. Furthen more it will be observed that each of the vertical frame members 9 as well as the lower frame member 8 is exposed on at least one side to radiation ,to the relatively cool metal walls of the housing 3, whereas in constructions in which metal parts are located within the cross section of the flue such parts are exposed to heat on all sides and there is no opportunity for cooling the same by radiation of heat therefrom.. In. my improved construction all metal parts. are therefore prevented from becoming ever heated, thus not only preventing damage or lot:

deterioration of said parts, but also preserving their full strength at all times and preventing weakening of the frame structure which might result if such parts became overheated.

My improved form of damper construction may be applied in connection with flues of any shape, for example to circular fiues, as well as to rectangular flues as shown in the drawings, suitable changes being made, if necessary, in the shape of the housing section 3 and the damper slab 12 in order to conform to the shape of the flue. Said housing must in any case, however, extend beyond the sides and bottom of the flue opening so as to provide recesses at these points adapted to contain the side and bottom members of the metal frame of the damper, and the recess thus formed below the flue should be of sufficient size to contain the damper when the same is moved out of the cross section of the flue, or to full open position. It should also be understood that my invention is applicable not only to horizontal lines, but to inclined flues' as well, provided such flues do not depart from a horizontal direction sufliciently to prevent eflective operation of a substantially vertically moving damper.

As shown in Figs. 1 to 4 inclusive the vertical frame members 9 may consist of round bars or rods and theupper and lower frame members 7 and 8 may comprisemetal bars, beams, or other structural members of suitable shape, the bottom frame member being preferably flat on top and of about the same width as the refractory slab or damper so as to provide an effective support therefor. Any other suitable type of metal frame con struction may be used however, for example as indicated in Figs. 5 and 6 the vertical frame members 9 may consist of T-bars arranged as indicated and such a construction provides for very effective cooling of such frame members. The refractory covering 18 for the vertical frame members may comprise, for example, blocks or bricks 22 of special shape and the notches 19 therein may be of such shape as to fit over and engage the sides of said members as at 23, so as to assist in holding said bricks in position.

Furthermore instead of relying upon radiation and natural convection for cooling the metallic housing of the damper, I may in some cases provide a jacket around said housing as indicated at 24 in Figs. 5 and 6 and circulate a cooling medium, such as water or air, through such jacket in any suitable manner. WVith such a construction the walls of the housing will be kept relatively cold at all times and the dissipation of heat from the metallic damper frame will therefore be much more rapid than when no cooling jacket is provided. It will also be seen that in case such artificial cooling means are used it will not be necessary to extend the housing out beyond the flue to provide for radiation of heat therefrom as in the form first described, and such housing may therefore if desired be embedded in the flue walls,

What I claim is:

1. A damper construction comprising in combination with a flue, fixed housing means extending beyond the side and bottom walls of said fine, a metal frame movably mounted within said housing and wholly outside the cross section of the flue, a damper consisting of refractory material supported upon said frame, and means for moving the frame and the damper supported thereby so as to move the damper into and out of position to close the flue.

2. A damper construction comprising in combination with a flue, housing means extending outwardly beyond said flue at the sides and bottom thereof so as to provide lateral recesses and a recess below the flue, a metal frame comprising vertical frame members extending within said lateral recesses and a lower frame member connecting said vertical frame members and extending within the recess below the flue, a damper consisting of refractory material mounted upon said lower frame member,

' and means for moving the metal frame and the damper so as to bring said damper into or out of position to close the flue, said re cess below the flue being of sulficient size to contain said lower frame member and the damper when the same is moved to open position.

3. A damper construction as set forth in claim 2, said recess below the flue being provided with means for discharging solid material therefrom.

4. A damper construction as set forth in claim 2, said vertical frame members being provided with protective coverings of refractory material on the sides of said frame members towards the flue.

5. A damper construction as set forth in claim 2, said vertical frame members being provided with protective coverings of refractory material on the sides of said frame members toward the flue, and said vertical frame members and the lower frame members being exposed on the sides of saidmembers away from the flue so as to permit dissipation of heat therefrom.

6. A damper construction as set forth in claim 2, said vertical frame members being provided with protective coverings of refractory material on the sides of said frame members toward the flue, and said lateral recesses extending upwardly above the top of the flue so as to permit movement therein of said protective coverings when the damper is raised within the flue.

7. A damper construction comprising, in

formed with combination with a portions side walls of the flue tending below the mounted to more so as to close the metal frame formed extendin wholly portions beyond the side and with botton inei'nbe vertical members and e within said housing porti and refractory means moi ported by said metal frame and adaoted to extend across said flue, and damper o constructed and mounted that within the flue consists at of refractory material a said.

operatin means connected to tik l Yeitica members and entendii a bore saie fine.

8. A damper consti c on eoniiprisfng, combination with a lie housing means formed with portions extending beyond the side walls of the flue one with a portion eX- eeasse tending below the flue and a damper mounted to move vertically in the housing so as to close the fine and comprising a metal frame and refractory means mounted on or sup-- ported by said metal frame, said metal frame having side members extending wholly within housing portions beyond the side walls of the flue and a bottom member e::tenng within the housing portion below the flue and said housing portion below the flue eing of sufficient depth to permit the refractory means on the damper to be lowered to position to open the flue or to be raised to position to close the flue while maintaining the lower metal frame portion wholly within said housing extension below the flue, and means connected to the said metal frame and extending wholly outside the flue, to support. and operate the damper.

In testimony whereof I have hereunto subscribed m name this 81st day of October, 1924.

WVALTER A. SCHMIDT. 

